A significant amount of power is consumed when lighting large areas such as parking lots, garages, and similar areas or structures. It is often desirable to reduce unnecessary power consumption to these areas when these areas are marginally used or not in use at all. However, owners of parking lots and garages are faced with several problems when attempting to reduce the significant power consumption of lighting these areas and the associated costs thereof.
Generally, lighting a large parking lot, for instance, comprises providing power to a plurality of lighting poles, each lighting pole having numerous powerful lights contained in lighting fixtures secured near the top of the lighting pole. Shutting off power to the lighting poles altogether after normal business hours use may be an option to reduce power, however, creates certain challenges. Although sparsely used during the late evening and midnight hours, parking lots and garages and the buildings they support are utilized by persons such as cleaning personnel, employees working late, etc. Moreover, laws and regulations in certain jurisdictions require specific foot candles of light to be evenly distributed on any parking lot or similar structure or area. Hence, owners may be liable for property damage or injury to persons rightfully on the property (even trespassers in certain situations) occurring under lighting conditions below standards.
Often, power to an entire parking lot or garage is turned on or off with a time clock mechanism utilizing a mechanical motor and contacts at the main power distribution feed. Power is supplied to all lights in the parking lot throughout the evening until morning, and then power is shut off to all lights at a specific time in the morning. In some situations, a photocell switching device is used at the main power distribution feed to turn power on to all lights in the parking lot at dusk and to turn power off to all lights at dawn. While proving more than sufficient lighting throughout the evening until morning, the use of a time clock mechanism or a photocell switching device does not allow for energy saving during the late evening and early morning hours of limited to no use in the associated parking lot or garage.
Complex power management schemes may be employed to some efficacy in reducing power. However, complex power management schemes typically require one or more costly and complicated power control systems to actively manage and significant retrofitting of the power distribution means including but not limited to tearing up asphalt and running new conduit and power/control cable throughout the parking lot.
Heretofore, a cost-effective and simple solution to reduce power consumption in parking lot, garages, and similar areas or structures remains elusive. In particular, it would be desirable to achieve substantial cost savings through reduced power consumption of lighting systems while maintaining a safely lit area during off peak usage of parking lots and garages with minimal capital, labor, and maintenance costs. Consequently, improved power management devices and techniques that are both simple and cost-effective requiring little to no continued maintenance activity are sought by owners and property managers of parking lots and garages.